package com.shiro.reml;

import org.apache.shiro.authc.AuthenticationInfo;  
import org.apache.shiro.authc.AuthenticationToken;  
import org.apache.shiro.authc.ExcessiveAttemptsException;  
import org.apache.shiro.authc.credential.HashedCredentialsMatcher;  
import org.apache.shiro.cache.Cache;  
import org.apache.shiro.cache.CacheManager;

import java.util.concurrent.atomic.AtomicInteger;  

public class RetryLimitHashedCredentialsMatcher extends HashedCredentialsMatcher {  
  
    private Cache<String, AtomicInteger> passwordRetryCache;  
  
    public RetryLimitHashedCredentialsMatcher(CacheManager cacheManager) {  
        passwordRetryCache = cacheManager.getCache("passwordRetryCache");  
    }  
  
    @Override  
    public boolean doCredentialsMatch(AuthenticationToken token, AuthenticationInfo info) {  
        String username = (String)token.getPrincipal();  
        //retry count + 1  
        AtomicInteger retryCount = passwordRetryCache.get(username);  
        if(retryCount == null) {  
            retryCount = new AtomicInteger(0);  
            passwordRetryCache.put(username, retryCount);  
        }  
        if(retryCount.incrementAndGet() > 5) {  
            //if retry count > 5 throw  
            throw new ExcessiveAttemptsException();  
        }  
  
        boolean matches = super.doCredentialsMatch(token, info);  
        if(matches) {  
            //clear retry count  
            passwordRetryCache.remove(username);  
        }  
        return matches;  
    }  
}  